Influence of Different Three-Dimensional Open Porous Titanium Scaffold Designs on Human Osteoblasts Behavior in Static and Dynamic Cell Investigations

Abstract

In the treatment of osseous defects micro-structured three-dimensional materials for bone replacement serve as leading structure for cell migration, proliferation and bone formation. The scaffold design and culture conditions are crucial for the limited diffusion distance of nutrients and oxygen. In static culture, decreased cell activity and irregular distribution occur within the scaffold. Dynamic conditions entail physical stimulation and constant medium perfusion imitating physiological nutrient supply and metabolite disposal. Therefore, we investigated the influence of different scaffold configurations and cultivation methods on human osteoblasts. Cells were seeded on three-dimensional porous Ti-6Al-4V scaffolds manufactured with selective laser melting (SLM) or electron beam melting (EBM) varying in porosity, pore size and basic structure (cubic, diagonal, pyramidal) and cultured under static and dynamic conditions. Cell viability, migration and matrix production were examined via mitochondrial activity assay, fluorescence staining and ELISA. All scaffolds showed an increasing cell activity and matrix production under static conditions over time. Expectations about the dynamic culture were only partially fulfilled, since it enabled proliferation alike the static one and enhanced cell migration. Overall, the SLM manufactured scaffold with the highest porosity, small pore size and pyramidal basic structure proved to be the most suitable structure for cell proliferation and migration.

Specific Yielding of Selective Laser-Melted Ti6Al4V Open-Porous Scaffolds as a Function of Unit Cell Design and Dimensions

“…Geetha et al [33] discussed the biomechanical compatibility, thermomechanical processing and surface conditions of many metallic materials. In reference [41], the author cultured human osteoblasts under static and dynamic conditions with results that confirmed the suitability of open-porous structures for biomedical applications.…”

Selective laser melting processed Ti6Al4V lattices with graded porosities for dental applications

“…Nevertheless, Markhoff et al evaluated the metabolic activity of human osteoblast cells on porous titanium scaffolds with cubic, pyramidal and diagonal basic structures under static and dynamic culture. They reported a significantly higher metabolic cell activity on pyramidal basic structure scaffolds with 400-620 µm pore size and 75% porosity with no significant differences between the culture methods [40]. In another in vitro observation, human osteoblasts cells were cultured on direct laser formed Ti-6Al-4V porous scaffolds with 500, 700 and 1000 µm pore size, after 14 days of cell culture cells covered most of the pores with 500 µm pore size.…”

Porous Titanium for Dental Implant Applications

“…Additive manufacturing technology was used to produce different pore geometries (cubic, diagonal, pyramidal), and static and dynamic culture methods were used. Interestingly, there were no significant differences between the static and dynamic cultivation methods, but cell activity and migration were best in the pyramidal design with a 400-620 µm pore size and 75% porosity [90].…”